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Note 4 - Other Long-term Assets | 12 Months Ended
--- | ---
Dec. 31, 2022
Notes to Financial Statements |
Other Assets Disclosure [Text Block] | (4) OTHER LONG-TERM ASSETS (IN THOUSANDS)
|  | December 31, |
|  | 2022 |  |  | 2021 |
Advanced coal royalties |  | $ | 5,967 |  |  | $ | 6,678 |
Other |  |  | 1,618 |  |  |  | 1,694 |
Total other assets |  | $ | 7,585 |  |  | $ | 8,372 |

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- Definition The entire disclosure for other assets. This disclosure includes other current assets and other noncurrent assets. + References No definition available. + Details
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